Written by: Certified Arborist August Hoppe, WI-0477A
Trees are good. Most of us understand that. We value trees for the oxygen they create,
shade on a hot summer day and the beauty they provide to our landscapes. These basic
qualities seem to be self-evident, even as many of us take for granted the ubiquitous
nature of our trees every day. Exciting new research in the realm of public health and
trees is showing that the value of trees runs even deeper than first known. Having
gardens, parks and trees in our landscapes leads to higher quality of life.
Research shows that individuals experience reduced stress levels with more frequent
and longer visits to green spaces. Exposure to nearby nature can effectively reduce stress. Even just having a view of nature from a window can have restorative effects on
our health. Outdoor activities can help alleviate symptoms of Alzheimer’s, dementia, stress, depression and improve cognitive function in those recently diagnosed with cancer. Contact with nature helps children develop emotional and behavioral connections to their environments. Nature experiences are important for encouraging imagination and intellectual development, and social relationships.
The experience of nature and trees helps to restore the mind from the mental fatigue of
work, contributing to improved performance and job satisfaction. Research has found that city residents who live adjacent to green space have lower levels of illness and disease than other people of similar income levels. Physical environments that promote good health may reduce socioeconomic health inequalities.
Economists and scientists have devised reliable methods to represent the value of trees
and open spaces in cities and towns. The presence of larger trees in yards and as street
trees can add from 3% to 15% to home values throughout neighborhoods. Homes that
are adjacent to natural parks and opens spaces are valued at 8% to 20% higher than
comparable properties. Commercial offices with high-quality landscapes have 7%
higher rental rates. Shoppers indicate that they will travel greater distances to visit a
shopping center having high-quality trees, and spend more time once they arrive.
The most recent research suggests that trees may improve driving safety. One study found a 46% decrease in crash rates across urban street and highway locations after landscape improvements were installed. There is less graffiti, vandalism and littering in outdoor spaces with natural landscapes than in comparable spaces without plants. Public housing residents with nearby trees and natural landscapes reported 25% fewer acts of domestic aggression and violence. Studies of residential neighborhoods found that property crimes were less frequent when there were trees in the right-of-way and more abundant vegetation around a house.
The value of trees for our properties and in our community continues to grow. Yet, currently due to Emerald Ash Borer, and other insects and diseases of trees, we are losing large mature trees at a rate not seen since the Dutch Elm Disease crisis of the 1970s and 1980s. Planting new trees to fill the void is an important task to restoring our lost canopy cover. However, maintaining the health of our existing mature trees provides the biggest value.
As arborists that care for trees, we take pride in maintaining this valuable green infrastructure and leaving a legacy with every tree that we work on.
Sources cited in this article appeared in Green Cities: Good Health, a collaboration between the US Forest Service and the University of Washington.